Heating & Cooling

Establish a preventative maintenance program for your heating, venting and air conditioning
(HVAC) equipment and systems. Maintenance activities can save up to 30% of fan energy and
up to 10% of space conditioning energy use.

Ensure that you regularly:

Change or clean all air filters, preferably every month.

Clean all heat exchanger surfaces, water and refrigerant coils, condensers and evaporators.

Repair leaks in piping, air ducts, coils, fittings and at the unit(s).

Replace defective equipment insulation, ducting and piping.

Install a high efficiency packaged heating, ventilation and air conditioning (HVAC) system.
These can use up to 40% less energy than systems that just meet minimum standards. Look for
a high SEER (Seasonal Energy Efficiency Ratio) or, on larger units, EER (Energy Efficiency Ratio).
You can purchase units with SEER above 12 or EER above 11. Specify high-efficiency air conditioning
equipment when your system needs to be replaced, and save 25% to 35% on your investment annually.

When old motors fail, replace them with premium efficiency motors that operate at a lower annual cost.
Ensure you specify the proper sized motor for the application.

Install variable speed drives (VSDs) on large motor loads, where appropriate, to further reduce energy usage.

Use outside air and water side-economizers for "free cooling" when outside air temperatures and conditions permit - during the spring and fall.

In facilities with older chillers, consider replacing them with new, energy-efficient units that operate at or below .60 kilowatts per ton.

Reduce air conditioning and heating hours by installing a timer to turn off the system when the building is unoccupied.

Add controls to exhaust fans. Exhaust fans remove air that has already been conditioned. Install timers and switches to shut them off when they are not needed or when the building is unoccupied.

Install an ENERGY STAR programmable thermostat to automate your HVAC system. An "old-fashioned" thermostat turns the HVAC on and off based on temperature, not whether the building is occupied, or whether you benefit from the cooling/heating. A programmable thermostat can optimize HVAC operation "24/7" based on your needs. For example, instead of heating or cooling all night, so you can enter a comfortable building in the morning, this "smart thermostat" can turn on the HVAC one hour before you arrive, based on your daily/hourly needs. The cost can be $25 to $150, and it could cut your HVAC costs about 30%. Add a locking cover to prevent tampering with thermostat settings.

Temperature control

Manage your thermostat. In winter, set office thermostat offices between 65 and 68 during the day/business hours, and 60 to 65 degrees during unoccupied times. In summer, set thermostats between 78 and 80 degrees during the day/business hours, and above 80 degrees during unoccupied hours.

Adjust thermostats higher when cooling and lower when heating an occupied building or unoccupied areas within a building, e.g., during weekends and non-working hours.

Install programmable thermostats that automatically adjust temperature settings based on the time of day and day of the week. If you have multiple HVAC units, set your thermostats to return to the occupied temperature a half an hour apart.

In larger facilities with energy management systems (EMS), verify that temperature set points and
operating schedules are correct for the controlled equipment. For EMS systems that no longer operate as initially designed, consider a retro-commissioning project to restore the system's functionality.